The GT1CD clutch for Toyota 86 uses a 'Hard' diaphragm spring which means improved torque capacity still with good drivability. It is suitable for turbo modified engines up to 280kW at the engine.

OS Giken GT single-plate clutches are built in the same manner as a multi-plate clutch, so the clutch cover, pressure plate, flywheel, housing and friction disc are all separate parts. This means they can easily be overhauled in the future, but more importantly, the arrangement of the OS Giken diaphragm creates much better clamping on the pressure plate without excessive pedal weight.
The light chrome-moly flywheel and billet aluminium cover plate also improve engine response. This clutch uses a 215mm clutch disc and comes with the bearing/carrier set needed for installation.
The most important innovation of the new GT series clutches, however, is the exclusive 'floating pressure plate' system (patent pending). A series of leaf springs between the pressure plate and the clutch diaphragm achieve a very smooth initial take-up, just like a factory-style clutch. It can be held in a half-engaged, slipping state very easily, so you can drive very easily around town. This system also eliminates the 'rattle' sound associated with the older 'Super Single' design.